Acute Intermittent Porphyria

History

Fact

Explanation

Classic triad of symptoms during acute exacerbations [1,4,6]

A triad of symptoms, abdominal pain, psychiatric symptoms (hysteria, hallucinations, paranoia) and pheripheral neuropathy occurs. Abdominal pain is usually colicky and severe, mostly involves the epigastrium and lasts for several days. Nausea and vomiting may also be present.

Patients may complain of urinary retention, incontinence, and dysuria. [1]

History of exposure to a precipitant

Usually this autosomal dominant disease does not manifest until second or third decade of life, because some activity of the enzyme (porphobilinogen deaminase) remains. Some precipitants may cause exacerbations and also may cause early presentation. Common precipitants are fasting, dehydration, stress and infection. Physiological hormonal fluctuations (menstruation and pregnancy) may also act as a precipitant. [3] Barbiturates and steroids are common precipitant drugs. [5]

Examination

Tachycardia or bradycardia [4] and arrhythmias occur due to autonomic neuropathy. [1]

Blood pressure[2]

Hypotension or hypertension can occur secondary to autonomic neuropathy. [4]

Motor neuropathy

Mostly lower limb muscle groups are paralyzed. Patients can have quadriparesis as well. [3] Lower motor type paralysis is seen. (The muscle tone, power and reflexes are either absent or diminished, the extensor plantar response is absent)

These include hereditary coproporphyria (HCP), variegate porphyria (VP) and ALA dehydratase deficient porphyria (ALAD). All these three porphyrias characteristically present with neurological symptoms. [1] HCP and VP are collectively known as neurocutaneous porphyrias and cause skin rashes in sun-exposed areas.

Lead Nephropathy

Exposure to lead causes systemic hypertension and nephropathy which is worsened by the hypertension. [4]

Familial mediterranean fever

hypertension. [4]
Familial mediterranean fever usually present in the first decade of life. There is recurrent attacks of fever and painful polyserositis. The precipitants are more or less similar in both conditions. (stress, certain food, some drugs) [5]

Nephrolithiasis

Patients complain of severe pain radiating from loin to the groin and often to the testicle or to the labia. Some may have hematuria. [6]

Nerve Entrapment Syndromes

Cause sensory or motor neuropathies.

Constipation

Other causes of constipation should also come in differential diagnosis.